<!DOCTYPE html>
<html>
    <head>
        <meta http-equiv="content-type" content="text/html; charset=UTF-8">
        <meta name="viewport" content="width=device-width, initial-scale=1">
        <style type="text/css">
            body {
                margin: 0;
            }

            #outer {
                position:         fixed;
                width:            100%;
                height:           100%;
                background-color: rgb(255,0,0);
            }

            #inner {
                position:         fixed;
                top:              50px;
                left:             50px;
                right:            50px;
                bottom:           50px;
                background-color: rgb(0,255,0);
            }
        </style>

        <title>Crop screenshots</title>

    </head>
    <body>
        <div id="outer">
          <div id="inner"> </div>
        </div>
    </body>
</html>
